FIG. 5.

Release from G₁ arrest alleviates the transcriptional block at hsp82-ΔHSE1. (A) Experimental strategy. CBY101 cells were arrested in G₁ as for Fig. 3; an asynchronous culture (not indicated) was grown in parallel. At t = 0 h, galactose was added to each culture to induce HSF overexpression. At t = 1.5 h, the α-factor-arrested culture was split into three aliquots; one was washed and resuspended into medium lacking α-factor, one was washed and resuspended into medium containing α-factor, and the third was washed and resuspended into medium containing HU. The asynchronous culture was also harvested and resuspended into medium alone. Samples were removed at the indicated times and subjected to heat shock. (B) Plot of Northern data from the experiment depicted in panel A. (C) Immunoblot analysis. Total protein was isolated from aliquots of CBY101 cells subjected to the indicated treatments and harvested at the indicated times and then assayed for relative HSF concentration.